Span 45.5 cm / 18 in
Weight 28 g / 1 oz
The concept:
- Funny stubby design
- high-wing monoplane
- good flight characteristics
- few parts
- easy to build
- two versions, one rubber powered (here) the other RPU 20
Name not only sounds Spanish, it is and means in English: It costs less than you think.
Building the rubber powered balsa sheet model Cuesta menos de lo que crees.
Materials:
Fuselage: B 3; round nose parts: B 3 or 4 or 5; triangle shaped nose parts: B 3 or 4 or 5; wing: B 1; wing ribs: B 3; wing support: B strips 3 x 3; fin: B 1.5; horizontal stabilizer: B 1; linen band width 10-12 mm / ½ in; piano wire 1.2 or 1.5 mm diameter for hook; ballast: steel or lead.
Assembly:
Cut out balsa parts in accordance to plan. Sand well. Transfer outlines of cockpit, rudders, elevators etc. from paper to wood with pen. If coloring is desired do it now.
Fuselage:
Cement fin on fuselage. Visually check symmetry from all sides as both parts have to be 100 percent in line.
Bend wire to get it into hook shape as shown on plan. Carve bed for hook with a knife and a round file. Cement hook into bed. Cover area generously with a piece of linen and with an extra dose of glue.
Cement wing support strip at given place on one side of the fuselage holding with needles or clamps or clothespins. Let dry. Repeat procedure on the other side and let dry.
Cement round nose parts one on another. When dry sand into cone shape. Use balsa putty to fill gaps and sand well. Repeat this procedure, sanding and applying putty, if necessary.
When the nose part is smooth you can start to carve out opening which holds prop-bearing. Start from behind and do it not in a hurry. A little electric drill machine can be useful.
Cement nose cone on fuselage referring to photos. When dry add nose support triangle-shaped parts.
Wing:
Wing consists of a right and a left wing half. Fix left wing half on building board with needles. Underlay right wing half tip in accordance to required dihedral. Join both halves and cover wing center area with linen band. Let dry. Mark position of ribs on wing underside and cement ribs to wing. Use clamps to hold tight until cement is dry. If wing has the tendency to rest only on one side then it is too heavy on this side. To compensate the imbalance disperse an amount of white wood glue on the opposite wing half’s underside tip area. Do it if necessary twice until balance is obtained.
Final Assembly:
Put fuselage on “third hand”. Cement wing on fuselage and on wing supports using needles to hold in place. Doublecheck symmetry. Let dry.
Repeat procedure with horizontal stabilizer. Again check symmetry! Let dry.
Install rubber and 6 in airscrew. Test-glide your model over tall grass. Add ballast according to your test results. Note given position of CG on plan.
Remember a correct center of gravity (CG) is essential for successful flights.
Izan hegaldi atsegin asko! (Wielu przyjemnych lotów!)
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